a) Field of the Invention
The present invention relates to electromechanically actuated valves for an internal combustion engine, and more specifically relates to intake and exhaust valve assemblies used in the internal combustion engine.
b) Description of the Related Art
A Japanese Patent Application First Publication No. Heisei 9-256825 published on Sep. 30, 1997 exemplifies previously proposed intake and exhaust valve assemblies for an internal combustion engine.
In the previously proposed intake and exhaust valve assemblies, an armature integrally linked to each valve axle portion of the corresponding one of the intake and exhaust valves is operated by a cooperation operation of a pair of electromagnets, one electromagnet being energized to direct the valve axle portion in a valve open direction and the other electromagnet being energized to direct the valve axle portion in a valve close direction and both electromagnets being disposed in an actuator housing so as to be faced against upper and lower planes of the armature, respectively, and a pair of spring members, one spring member biasing the valve axle portion of the corresponding one of the intake and exhaust valves in the valve close direction. Consequently, each of the intake and exhaust valve can be opened or closed according to either electromagnetic force exerted by the one or the other of the pair of electromagnets.